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You can’t feel your heart rate. You remember it.
Set an implanted pacemaker to 61 beats a minute, ask the person to sit quietly and count the heartbeats they can feel, and they report about 52. Set the same pacemaker to 109 and ask again. They report 59.
The heart nearly doubled its rate. The count moved by seven.
That result sits in a 2016 review by Jasper Brener and Christopher Ring, two researchers who spent their careers trying to establish whether people can perceive their own insides at all. It is the most useful thing I know about body awareness, and almost nobody outside that literature has heard it.
Speed the heart up. The count stays where it was.
Ring and Brener ran the simpler version too, using posture instead of hardware. Lying down, their participants' hearts ran at roughly 70 beats a minute and they counted 50. Standing up — which reliably pushes heart rate higher, here to about 86 — they counted 48.
The heart gained sixteen beats a minute. The count lost two.
Whatever those participants were doing during that minute, it was not listening.
Figure 1 — what the count actually tracks
Speed the heart up and the count stays where it was
The same thing happens when posture does the work
The standard test measures arithmetic and self-image
The task in question is the heartbeat counting task, introduced by Rainer Schandry in 1981 and still the workhorse of the field. Sit still. Don't take your pulse. Count the beats you actually feel over a fixed interval. Compare your count to a real recording, and the gap is your "interoceptive accuracy."
In 1996 Ring and Brener took the obvious next step and asked people, beforehand, what they believed their heart rate did lying down, standing, and after exercise. Then they measured the counting. Counted rates sat closer to believed rates than to real ones, and belief still predicted the count after actual heart rate was statistically controlled for.
There is a second leak. Counts correlate with how well people estimate elapsed seconds — so someone with a decent internal metronome and a roughly correct idea of their own resting pulse can produce an impressive accuracy score having felt precisely nothing.
This is the awkward part, and it is worth saying plainly. A large literature linking "interoceptive accuracy" to emotion, eating and decision-making rests on a task that can be passed by mental arithmetic.
Three tests, three different sets of people
If the counting task were merely noisy, other cardiac tasks would still sort people the same way. In 2025 Eszter Ferentzi and colleagues checked, in Psychophysiology: 73 young adults, three established tests of the same supposed sense, all in one session.
Counting classified 27.4% of them as genuine heartbeat perceivers. A discrimination task classified 28.8%. A signal-detection task classified 12.3%. One person out of seventy-three cleared all three. Agreement between any pair of tasks ran from a kappa of 0.019 to 0.141 — close enough to chance to be indistinguishable from it.
The authors concluded the tasks "require different abilities" and are not interchangeable. That is the polite version. When three instruments built to measure one sense disagree almost completely about who possesses it, at least two of them are measuring something else.
In 2026, one lab named what it had actually built
This April, Jamie Moffatt, Markus Tünte, Mariana von Mohr and Manos Tsakiris published a new approach, also in Psychophysiology. Their Heart Rate Matching task shows you a pulsing animated heart and lets you speed it up or slow it down with the keyboard, anywhere from 30 to 130 beats a minute, until it matches your own. Roughly half a minute per trial, seven to twelve minutes in total, and it works at home over a webcam pulse signal rather than needing an ECG.
Across three experiments and some 170 participants, it held together: test-retest reliability for estimation bias came in at an ICC of 0.722. A usable instrument, in other words.
And then the authors wrote that it "should not be interpreted as an interoceptive accuracy task, but instead a task which measures beliefs about heart rate." Their own control condition had given them away — performance on the heart task tracked performance on an auditory rate-matching task, which points at general multi-sensory estimation rather than a private line to the chest.
Publishing that sentence about your own new instrument is the most respectable thing in this entire literature.
Accuracy is not awareness, and the gap is where the selling happens
Two different things get called body awareness. One is detection: can you register the beat. The other is what researchers call sensibility — how much you attend to bodily signals, how much you trust them, whether you use them to steady yourself. The second is measured with questionnaires, most often the Multidimensional Assessment of Interoceptive Awareness. The two are only loosely related.
Wellness culture sells the second while implying the first. Tune in. Listen to your body. As though there were a broadcast.
There is a broadcast. For most people, most of the time, it is not in a band you receive.
The part that does move when you work on it
In July, Frontiers in Network Physiology published a small study by Schumann and colleagues that is interesting precisely because of which number moved. Twenty-five healthy adults, average age 48, did eight weeks of home heart-rate-variability biofeedback: five sessions a week, breathing at their own resonance frequency, later synchronising each breath with the heart-rate wave on screen.
Counting accuracy rose from 43% to 51% — a real effect, and a small one (d = 0.39). On the questionnaire, Attention Regulation moved d = 0.49 and Emotional Awareness d = 0.44, but Self-Regulation moved d = 0.83, and it was the only subscale still standing after correction for multiple comparisons.
Eight weeks of deliberate slow breathing barely improved people's ability to count their own heart. It substantially changed how well they felt they could use their body to settle themselves. Those are different findings and they point the same direction.
The study cannot settle it, and it is better for admitting so. Twenty-five people, no control group. Spending eight weeks attending closely to your breathing and then filling in a questionnaire about how closely you attend to your body is exactly the design that manufactures a positive answer. The counting result is harder to talk yourself into — but it is also the smaller one. Both readings fit the data.
One cross-sectional detail is worth keeping. At baseline, people with a lower resting respiration rate scored higher on emotional awareness (r = −0.59), and people with a lower resting heart rate scored higher on self-regulation (r = −0.59). Which may mean slow breathing builds composure, or may simply mean composed people breathe slowly. Nothing in the design chooses between them.
What to do with a body that doesn't file reports
Try it once this week. Sixty seconds, sitting still, no pulse-taking, counting only the beats you genuinely feel — then compare against a measured heart rate. Most people land far under. That undercount is the normal finding, not a personal shortcoming, and knowing it changes how much authority you hand to your own sensations.
Demote "my heart is pounding" from fact to hypothesis. The feeling is real and worth attending to. The rate you've attached to it probably isn't. Racing hearts are felt most vividly by people who expect to feel them.
Then run it the other way. A flattering reading on a morning you feel wretched does not overrule the morning. This is the whole discipline: use numbers to correct fantasy, not to replace experience. A good HRV trend and a bad week are perfectly capable of coexisting.
And if you want to train something, train the breath. Around six breaths a minute, a few minutes, most days — the one lever here with both a plausible mechanism and supporting evidence. The honest version of the claim is that it changes your relationship to the signal more than your reception of it. We covered the mechanics in breathwork for stress.
Where measurement earns its place
This is the argument for wearing something, and also the limit of it. Your heart rate and its variability are genuinely informative and genuinely invisible to you; that combination is rare, and it is why the Agen Band tracks them continuously rather than asking you how you feel. It is also why we keep insisting that a single reading is a trend to notice, not a verdict — see what your wearable can and can't measure and what your resting heart rate actually means.
Measurement is not the opposite of body awareness. It is the correction to it, on the channels where awareness was never very good — which is most of them. The rest of the system is laid out in how to build a longevity protocol.
The bottom line
Almost nobody can feel their own heart rate. What they can feel is their expectation of it, which is why a pacemaker set to 109 produces roughly the same count as one set to 61. The sensible response is not to abandon the body's signals — they carry real information about effort, mood and strain — but to stop treating them as readings. Feel what you feel. Measure what you can't. Don't confuse the two, and be suspicious of anyone who tells you the answer was inside you the whole time.
